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Stalkers are not just creepy –– they can also inflict serious psychological harm, a new study has found. Researchers at Washington and Lee University have determined that women victimized by stalkers are up to three times more likely develop anxiety issues and mental distress. The findings may prompt more comprehensive prevention efforts as well as improved services for victims.

Published in the journal Social Science Quarterly, the study examined how persistent stalking affects a victim’s mental wellbeing. By analyzing past surveys, the researchers found that the stress of being watched and followed may lead to lasting health complications, regardless of whether physical contact is made. Timothy Diette, lead author and professor of economics at Washington and Lee, said that the findings may inspire a more serious public perception of the phenomenon.

“I think the major implication of our findings is that while not everyone takes stalking seriously because in most cases nothing physical happened, the detrimental impact is clear," Diette explained. "This study helps raise awareness that in many cases it's a really scarring event that causes real-life psychological outcomes for victims' mental health and their ability to function in society."

To investigate the link between stalking and mental health, the researchers analyzed three major surveys involving over 8,000 female victims, ages 12 to 45. The victims had all been stalked without sexual assault. Subjects were divided and examined in three different age groups: adolescence (12-17), early emerging adulthood (18-22), late emerging adulthood (23-29), and early middle age (30-45),

The team found that while subjects from all age groups exhibited a statistically significant increase in their likelihood of developing psychological distress, the heightened risk was particularly pronounced among women ages 23 to 29. Whereas women of early emerging adulthood and early middle age were about twice as vulnerable as their non-victim peers, women of late emerging adulthood were almost three times as likely to develop these issues. Diette and his colleagues theorized that the statistical spike is due to the concomitant surge in physical strength and sexual urge of the stalker. In other words, stalking victims ages 23 to 29 are more afraid because their stalkers tend to be more dangerous.

"The large negative effect on the mental health of victims was actually surprising to me," Diette said, speaking to Health Day. "In many cases where you have a gut reaction that of course there should be an effect, you may find that, after controlling for various elements, those effects are actually smaller than you had expected. That is not the case in this study."

Policy makers and health officials estimate that 12 percent of women will be victimized by stalkers at some point in their lives. Because of the difficulties of enforcing restraining orders, more than half of all cases go unreported. The team hopes that the new findings will help change this.